WASHINGTON -- When President Barack Obama ran for re-election, Democrats made no secret of their disdain for Mitt Romney. That was all before Donald Trump.

Horrified by the prospect of Trump in the White House, Obama and his party have changed their tune about Romney. As they denounce Trump as "unhinged" and unfit, they're getting nostalgic about the 2012 Republican nominee they now describe as principled, competent and honourable.

It's a sharp reversal from four years ago. Back then, Democrats spent hundreds of millions of dollars portraying the former Massachusetts governor as a callous, unpatriotic, pet-abusing caricature of the uber-rich.

Yet as Trump is proving, everything in politics is relative.

"He was in it for the right reasons," Stephanie Cutter, Obama's 2012 deputy campaign manager, said of Romney. "He truly believed in wanting to make this country better. We just differed significantly on how to do that."

Cutter said that in 2012 Democrats had ideological clashes with Romney, but didn't doubt his temperament or basic competence. She said unlike Trump, Romney didn't "insult his way through his campaigning," malign minorities, or threaten to violate the Constitution or to abandon U.S. allies.

New York Rep. Steve Israel, one of the Democratic Party's top campaign strategists, said "Romney was qualified, but he had the wrong ideas. Trump is unqualified, dangerous and still has the wrong ideas."

And Obama's 2012 campaign press secretary, Ben LaBolt, put it this way: "I don't think anybody would have truly expected the country to go to hell in a handbasket" if Romney had won. "Trump presents an entirely different level of threat," he said.

Rewind to 2012.

A pro-Obama super PAC aired a TV ad indirectly alleging that Romney caused a woman's death. Democrats accused him of animal cruelty over a decades-old story about Seamus, the family dog, forced to ride rooftop on a road trip. Vice-President Joe Biden told a largely black audience that Romney and his running mate were "going to put y'all back in chains."

All the while, Obama attacked Romney's business record ruthlessly, as Democrats questioned whether Romney's use of offshore accounts made him unpatriotic. Obama's campaign even suggested Romney might have committed a felony by misrepresenting his employment status to federal regulators.

It's this year's great irony that the same Democratic attacks that landed hard on Romney seem to bounce right off of Trump. Where Romney had to downplay his wealth, Trump boasts of his riches, and brushes off controversies over remarks perceived as insensitive to women or minorities.

Russ Schriefer, a top Romney adviser in 2012, said he hoped Democrats were learning that words matter, even in politics. He described a campaign equivalent of "The Boy Who Cried Wolf."

"Don't be surprised when your accusations against Trump are falling upon deaf ears and aren't working, when you've used them in the past against a person for whom the descriptions didn't fit," he said.

But Israel, who oversaw Democrats' efforts to win House seats that year, said he didn't think the attacks had gone too far. After all, Romney and Republicans were similarly tough on Obama, calling him a liar and a failed president.

"The rhetoric gets heated on both sides of the aisle in any campaign," Israel said.

Many Republicans, too, have declared Trump dangerous and unsuitable for the Oval Office. Chief among them is Romney, who implored fellow Republicans during the primary not to nominate Trump and called him a phoney, a fraud, a bully and a con man.

"I have never seen anything like it, and kudos to Romney for having the courage of his convictions when it comes to Trump," said Dan Pfeiffer, Obama's White House communications director during the campaign.

These days, even Obama seems to acknowledge that Romney wouldn't have been awful -- at least not compared to Trump. Earlier this month, Obama said he would have been disappointed had he been defeated by Romney in 2012 or by Sen. John McCain in 2008, but never questioned either Republican's ability to do the job.

A representative for Romney declined to comment on Democrats' newfound affection. But Eric Fehrnstrom, a longtime Romney adviser, called it an attempt to make GOP voters more comfortable with the idea of voting for Clinton.

"He knows whatever expressions of support for him now coming from Democrats are purely political," Fehrnstrom said. "They're totally insincere."